Optical wavelength detection of narrowband signals (e.g., optical signals having a narrow bandwidth of wavelengths) is widely useful for many applications including, but not limited to, optical sensing and metrology. For example, optical sensors based on Bragg gratings may output a narrowband optical signal where the wavelength is directly related to a measured property of interest. Such sensors may be utilized by detecting the wavelength of the output light and correlating the wavelength to the property of interest based on a calibration curve, a lookup table, one or more calculations, or any other desired technique. Further, it is desirable in many applications to achieve fast and accurate wavelength detection over a wide optical wavelength range.